Determination of unsaturated structures in poly(vinyl chloride) by means of fourier transform 1H‐NMR spectroscopy

Abstract

AbstractA method based on the PFT‐NMR technique was developed for a direct determination of unsaturated end groups in PVC. By using NMR proton spectra it was found that the unsaturated groups in PVC contain allylic chlorine atoms. Three types of unsaturated end groups were identified, corresponding to the following models: 3‐chloro‐1‐pentene, 2,3‐dichloro‐1‐pentene, and 1,2‐dichloro‐2‐pentene. The last two types could also correspond to some unsaturated groups on the backbone bearing allylic chlorine atoms. The presence of such groups would partially explain the PVC degradation.